Technical options for heavy duty vehicles

Transcription

1 Technical options for heavy duty vehicles Tom Hazeldine (AEA) Ruben Sharpe (TNO) Session 1a July 3, Brussels 1

2 Options overview Engine improvements (~5%) Hybrid propulsion (~15%) Most efficient for buses and distribution trucks Alternative fuels/drive trains Reduction of energy requirements per vehicle Low rolling resistance tyres (~6%) Improved aerodynamic properties (~6%) Truck/trailer shape (legal requirements) Most efficient for long haul transport Lightweight construction (~7%) Lightweight design/lightweight materials Buses and distribution trucks Weight of the vehicle versus the weight of the load Role of inertia w.r.t. vehicle dynamics Long haul Reduction of CO2 per tonne-kilometer Reduction of energy requirements per tonne-kilometre (~9-20%) Increasing the weight limit (e.g. to 44 or 60 tonne) Elongation (road trains?) 2

3 Options overview Engine improvements??? Hybrid propulsion Improved aerodynamic properties Lightweight construction Low rolling resistance tyres Reduction of energy/tonne-kilometre Alternative fuels Alternative drive trains 3

4 Considerations for HD The reduction potential for HD is limited by: HD vehicles are already designed with fuel efficiency in mind HD vehicles have relatively low power to weight ratio Trailers have a long service life (~20 yrs) Slow penetration of new technology In the short term, emission legislation (Euro VI) somewhat counteracts the CO 2 reduction potential Elongation and an increased weight limit require legislative changes Capacity increasing options reduce the cost of transport Consequential increases in transport counteract environmental gains Specification Hybridization/aerodynamics Weight reduction because of lower requirements for structural strength Segmentation of legislative issues? 4

5 HGVs Alternative energy carriers Electric traction Potentially the least carbon intensive option Smith Electric Vehicles have developed a 12tonne EV truck (price is 74k to 80k) In the medium term applicability is limited to HGVs travelling modest distances due to: Requirement for a large, expensive battery pack Limited range Lack of widespread charging infrastructure Hybrid traction Greater medium term potential for hybrid HGVs than electric HGVs Fuel savings from regenerative braking and stop-start functions (up to 20% in urban areas, Infras 2007) Much smaller (and hence cheaper) batteries than a pure electric HGV Volvo hybrid trucks already being trialed E.g. Veolia is leasing 4 hybrid rubbish collection trucks in the UK and France Marginal capital cost is 153Euro/tonne of CO2 abated, Infras

6 HGVs continued Hydrogen/fuel cells Very unlikely to see commercial applications for forseeable future Cost, durability and power density are all issues with fuel cells Hydrogen is less energy dense than diesel therefore lower range Would require a new refuelling infrastructure Perceived safety risk (although less flammable the gasoline and would float away if leaked) CNG/LNG/LPG NG engines are 5% to 25% less fuel efficient than diesel (INFRAS, 2007) but NG is less carbon intensive so GHG emissions are similar Strong air quality benefits Already NG trucks on the road e.g. UPS has 800 worldwide NG HGVs are typically more expensive to purchase (~25%) but cheaper to run NG is less energy dense than diesel so NG HGVs have a lower range Lack of widespread refuelling infrastructure is a barrier Dual fuelling has more potential It can still run as a diesel truck, which negates infrastructure issue Manufacturer claims it reduces operating cost by up to 24,000 assuming 200,000km Manufacturer claims CO2 emissions reduced by 20% per year based on 90% diesel substitution Existing vehicles can be retrofitted 6

7 HGVs continued Biofuels 10% blend will be mandated by EU Renewable Energy Directive by 2020 Concern regarding the impact a higher percentage would have on engines Potentially, very significant GHG reductions 38% to 64% GHG savings for biodiesel from oilseed rape Significantly more expensive than conventional diesel Sustainability issues First generation biofuels use food crops Emissions savings are country-specific Direct and Indirect Land Use Change can increase emissions elsewhere Increased fuel consumption Decreased power 7

8 Buses Alternative energy carriers Electric traction Battery cost is a key barrier According to Transport for London, not currently able to meet operational requirements (18 hours per day), Recharging is less of an issue since most buses are captive fleets so only require one set of infrastructure A long term option once battery technology improves Hybrid traction Well suited to the stop-start bus drive cycle Many hybrid buses already in service (e.g. 60 in London, Vienna) but not yet mass production 40% price premium (Volvo) 20% 30% reduction in fuel consumption and hence GHG emissions (Volvo) Payback of 4 to 7 years 8

9 Buses continued Hydrogen/fuel cells Hydrogen fuel cell buses already trialled in Europe during 3 year CUTE project ending in December 2005 Buses operationally available 90% of the time Transport authorities are purchasing hydrogen buses in small numbers Transport for London plan to buy 10 AC Transit in US is buying 12 for $28million (I.e. $2.33million per bus vs ~$350k to $400k for a diesel bus) The marginal capital cost means they will be a long term option Perceived safety risk CNG/LNG/LPG Similar GHG emissions to diesel Buses are more expensive to purchase (~25%) But cheaper to run Lower range than diesel bus Lack of widespread refuelling infrastructure is a barrier 9

10 Buses continued Biofuels/Biogas Biofuels Similar pros and cons to HGVs Biogas Can be produced from various sources Landfill sites, human waste, kitchen waste etc For example, Oslo will be running 80 buses on bio-methane captured from a sewage plant Schemes to make use of biogas will tend to make use of local waste resources Synnergies between efforts to reduce waste and climate change goals GHG reductions ~44 tonnes per bus at the Oslo project taking account of electricity usage at the sewage plant Reduced fuel costs Price for Oslo biogas is around 0.27 Euro per litre vs 0.67 Euro per litre for diesel (Jan 2009) NG buses are more expensive 10